Dendritic cells (DC), antigen-presenting cells capable of priming naive T cells to specific antigens in an HLA restricted fashion, have been demonstrated to induce protective T cell-mediated immunity in tumor-bearing animals. We performed this study to test the safety, feasibility, and clinical response of immunizations within vitro-generated DC, loaded with an HLA A2 restricted peptide fragment of the tumor antigen carcinoembryonic antigen (CEA), for the treatment of patients with advanced CEA-expressing malignancies. Cell preparations enriched for autologous DC were generated from the patients' plastic adherent peripheral blood mononuclear cells (PBMC) in serum-free media supplemented with GM-CSF and IL-4.